Vogtle Nuclear unit reaches key startup test sequence

The Vogtle Unit 3 nuclear reactor achieved initial criticality, a key step in the startup testing sequence, Georgia Power announced last week.

The milestone means operators have safely started the nuclear reaction inside the reactor, atoms are being split, and nuclear heat is being made, officials said. Once the reactor achieves criticality, when nuclear fusion becomes self-sustaining, the reactor is in its first phase of generating heat to produce electricity.

“We remain focused on safely bringing this unit online, fully addressing any issues, and getting it right at every level. Reaching initial criticality is one of the final steps in the startup process and has required tremendous diligence and attention to detail from our teams,” said Chris Womack, chairman, president and CEO of Georgia Power. “When you consider the history of safe and reliable operations at Vogtle Units 1 and 2 for decades now, it puts today’s milestone in perspective that Plant Vogtle will be a four-unit site making it the largest of its kind in the U.S. This is a truly exciting time as we prepare to bring online a new nuclear unit that will serve our state with clean and emission-free energy for the next 60 to 80 years.”

Vogtle Unit 3 will continue with startup testing, Georgia Power said, that demonstrates the operation of the coolant system and steam supply system at high temperatures and pressures with fuel inside the reactor. Next, operators will raise power to support synchronizing the generator to the electric grid and begin producing electricity. After that, operators will increase power gradually until the reactor is at 100 percent.

Officials said the tests are designed to ensure all operating systems are working together and to validate procedures before the company declares Commercial Operation. The projected in-service date for Unit 3 is in May or June 2023.

Once fully operational, the Vogtle units will provide clean, safe, reliable, and affordable energy to Georgia Power’s 2.7 million customers and are expected to power more than half a billion homes and businesses. Southern Nuclear will operate the units on behalf of Georgia Power, MEAG Power, and Dalton Utilities.